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Gambardier: Heavy artillery crewman, often specifically a member of the Royal Garrison Artillery.
GAR: Groupes d'armées de reserve.
Garde à vous! : French for 'attention!'.
Gas Bag: Airship.
Gasper: inexpensive cigarette.
Gaspirator: British shorthand version of gas-respirator.
GDR: Groupe de Divisions de Réserve, French corps of reserve divisions.
Gearsman: The tank crewman who operated the gears.
Gebirgsschützen : Austrian mountain troops.
Geese: Slang for the Portuguese.
Gefreiter: Lance-corporal, German army.
Gekofunk: Commander of a German corps HW wireless unit.
General der Infanterie: German General from, but not necessarily commanding, the infantry.
General der Artillery: German General from, but not necessarily commanding, the artillery.
General der Kavallerie: German General from, but not necessarily commanding, the cavalry.
Generalfeldmarschall: German field marshal.
German Army Air Service: Aviation branch of the German army.
GHQ: General Headquarters.
Gimnastirka : Russian army shirt.
Gippy: Colloqiual term for Egyptians.
Girdle: tank tracks.
Glasshouse: (Military) prison.
Gloata : Romanian Landsturm.
Gnole: French slang for brandy.
Gobbler: Colloqiual term for Turks.
GOC: General Officer Commanding.
Gooseberry: Barbed wire, either on a reel or set up to entangle.
Gorblimey: A Field Service Cap with wire stiffeners removed.
Gorgeous wrecks: Army slang for the Home-Defence Corps.
Gotha: Used as slang for any large german bomber.
Gotha G-Types: German bomber biplane used from 1915.
Gotha WD-XIV: German torpedo bomber biplane in use 1917-18.
GPAR: Grand Parc Automobile de Réserve, French base motor park.
GPF: Grande Ouissance Filloux, French 155mm Filloux gun.
GQG: Grand Quartier Général, French General HQ.
GQGA: Général Quartier-Général des armées Alliées, General HQ of Allied Forces in France.
Granatenwerfer : German grenade throwing device.
Grand blessé: French for seriously wounded.
Grand-garde: French supporting party.
Grand Fleet: The main strike force of the British navy, based in Scapa Flow throughout the war and numbering over fifty craft.
Great Powers: Term for those nations deemed responsible by contemporaries for the world thanks to their considerable power. There was no set criteria, but the British, French, German and Russian empires, as well as the United States were included.
Great Programme: Official plan for the expansion and improvement of the Russian army in 1914.
Great Retreat: 1. Russian: The Russian withdrawal from Poland in 1915 moving the front line 350km east. 2. German: the German withdrawal in 1914 to entrenched positions. 3. Serbian: the evacuation of the Serbian army from its homeland in late 1915.
Greca: special kind of lace worn by Italian staff.
Green cross: German trichlormethyl gas shell.
Grenades: Small bombs either thrown by hand or fired from the end of a rifle.
Grenzjäger : Austro-Hungarian rifle corps.
Greyback: British army shirt.
Great Push: A term given to the Somme Offensive.
GRO: General Routine Order.
Grofv: Grossflammenwerfer, German heavy flamethrower.
Grufl: Gruppenführer der Flieger, German corps commander of the aviation service.
Grufusta: Gruppen-Funkenstation, German corps HQ wireless station.
Grukonach: Signals commander at Army Group HQ in the German army.
GS: 'General Service', any officially issued item.
GSO: General Staff Officer.
GSW: Gunshot Wound.
Guard Army: Elite Russian force numbering around 60,000 infantry and cavalry trained specially for an assault in 1916. It was trained in outdated methods and failed in its mission.
Gulasch-Kanone: 'Stew-gun', a German field kitchen on wheels; acquired its name because, when the chimney was lowered for transport, it looked liked an artillery piece.
Gunfire: Besides the usual, slang for early morning tea.
GV: Garnisonsverwendungsfahige, fit only for garrison duty.